Peer-to-peer (P2P) proximity communication may refer to infrastructure-based or infrastructure-less communications between peers within proximity of each other. A peer may refer to a user or a device such as, for example, a mobile station (MS) in a 2G system, or a full-function device (FFD) or reduced-function device (RFD) in a IEEE 802.15 wireless personal area network (WPAN). Examples of P2P devices include connected cars, medical devices, smart meters, smart phones, tablets, laptops, game consoles, set-top boxes, cameras, printers, sensors, home gateways, and the like. P2P proximity communication may focus on a peer being aware of its proximity to desired services in an infrastructure-based or infrastructure-less configuration. For example, P2P communications may be implemented in a centralized system that includes a centralized controller or a fully distributed system without a central controller. In contrast to infrastructure-less P2P communications, infrastructure-based communications often include a centralized controller, for example, for handling user information, scheduling among users, and managing connections (e.g., cellular communications). In infrastructure-less P2P communications, peers typically have equal responsibility for initiating, maintaining, and terminating a communication session.
Proximity-based applications and services represent a recent socio-technological trend to offload heavy local internet traffic from a core infrastructure as well as provide the connections to an infrastructure via multi-hopping. Many standards have identified proximity services use cases as part of their standardization working groups, such as 3GPP, oneM2M, IETF, IEEE, and OMA. Service layer, as well as cross-layer techniques, is an area of standardization to enable these services. P2P proximity communications are used in various applications including, for example, social networking, advertising, emergency situations, gaming, smart transportation, and network of network scenarios.
In typical social network implementations, peers in proximity can interact with each other at the application level (e.g., Facebook, Twitter). Two-way communication among two or more peers is often required in social network implementations of P2P proximity communications. Traffic data rates may be low (e.g., text-based chatting) or high (e.g., content sharing). In an example advertising implementation of P2P proximity communications, a store broadcasts its promotions and coupons to potential customers (peers) who are within proximity to the store's location. In this example scenario, one-way communication with low data traffic is typical, but two-way communication may be used (e.g., for personalized advertisements).
Implementation of P2P proximity communications in emergency situations usually involves one-way communication, such as an emergency alarm for example. Other emergency implementations need two-way communication, such as during an emergency safety management scenario. An emergency service/application of P2P may have higher priority than other P2P services/applications, and some emergency services/applications may have higher privacy requirements. In an example gaming implementation of P2P, multiple peers initialize or participate in interactive games, such as online multiplayer gaming following certain rules for example. Interactive P2P gaming often requires low latency. In an example smart transportation implementation of P2P proximity communication, connected cars, via car-to-car and/or car-to-infrastructure communication, can support advanced applications including, for example, congestion/accident/event notification, interactive transportation management such as carpooling and train scheduling, smart traffic control, and the like. Data rates in smart transportation implementations are often low, but smart transportation may require highly reliable message delivery and very low latency. Network-to-Network P2P may be used for extending the coverage of an infrastructure or offloading from the infrastructure.
IEEE 802.15.8 aims to specify Physical layer (PHY) and Medium Access Control (MAC) protocols for fully distributed peer-aware communications to support the emerging services discussed above, including social networking, advertising, gaming, streaming, emergency services, and the like. Some of the features of IEEE 802.15.8 include (i) discovery for peer information without association, a typical discovery signaling rate of greater than 100 kbps, and the ability to handle a number of devices in the discovery of more than 100 devices, (ii) scalable data transmission rates of, e.g., typically 10 Mbps, (iii) group communications with simultaneous membership in multiple groups (typically up to 10), (iv) relative positioning, multi-hop relay, security, and (v) operational in selected globally available unlicensed/licensed bands below 11 GHz and capable of supporting these requirements.